Merge branch 'develop' into feature/statistics-api

# Conflicts:
#	internal/backend/music.go
#	internal/backend/sync.go
#	internal/server/server.go
#	internal/server/syncHandler.go
#	internal/server/sync_handler_test.go
#	internal/server/test_helpers.go
#	internal/server/zz_music_handler_test.go

internal/server/syncHandler.go

@@ -49,6 +49,7 @@ func (s *SyncHandler) SyncSoundtracksNewOnlyChanges(ctx *echo.Context) error {
 		return ctx.JSON(http.StatusLocked, "Syncing is in progress")
 	}
 	logging.GetLogger().Info("Starting sync with only changes")
+	backend.Syncing = true
 	go backend.SyncSoundtracksNewOnlyChanges()
 	return ctx.JSON(http.StatusOK, "Start syncing soundtracks")
 }
@@ -68,6 +69,7 @@ func (s *SyncHandler) SyncSoundtracksNewFull(ctx *echo.Context) error {
 		return ctx.JSON(http.StatusLocked, "Syncing is in progress")
 	}
 	logging.GetLogger().Info("Starting full sync")
+	backend.Syncing = true
 	go backend.SyncSoundtracksNewFull()
 	return ctx.JSON(http.StatusOK, "Start syncing soundtracks full")
 }